Hi moondaddy,

Thanks for your post!!

Based on my understanding, you placed many Biz class objects in an list(I
suspect it is ArrayList? ), then you binds this list as datasource to the
TextBox, you want to get the function that: whenever the user pressed a
key, the datasource is updated.

For this issue, we can intercept TextBox's TextChanged event and force the
current edit to end. To get this done, we can use EndCurrentEdit method,
sample code snippet lists below:

private ArrayList al=new ArrayList();
private void Form1_Load(object sender, System.EventArgs e)
{
    for(int i=0;i<5;i++)
    {
        Biz obj=new Biz();
        obj.prop="Item"+i.ToString();
        al.Add(obj);
    }

    this.textBox1.DataBindings.Add("Text", al, "prop");
    this.textBox1.TextChanged+=new EventHandler(textBox1_TextChanged);

           this.timer1.Interval=2000;
    this.timer1.Start();
}

private void textBox1_TextChanged(object sender, System.EventArgs e)
{
    this.textBox1.DataBindings["Text"].BindingManagerBase.EndCurrentEdit();
}

private void timer1_Tick(object sender, System.EventArgs e)
{
    Console.WriteLine(((Biz)al[0]).prop);
}

public class Biz
{
    private string _prop="abc";
    public string prop
    {
        get
        {
            return _prop;
        }
        set
        {
            _prop=value;
        }
    }
}
It works well on my side. Note: in the sample, I used a Timer component to
dynamically get the datasource value, if we press a new character in the
textbox, we will see that the datasource is changed immediately.
=======================================================================
Thank you for your patience and cooperation. If you have any questions or
concerns, please feel free to post it in the group. I am standing by to be
of assistance.

Best regards,
Jeffrey Tan
Microsoft Online Partner Support